Deadly Obsession
by Pixil-8
Summary: It wasn't fair. Rika sent her for me. I deserved her- I had the right to her. Rika was my family, my flesh and blood. Nobody else should have her but me. I won't let them. I won't let anybody take her from me again. (Rated M for explicit gore, and character death.)


Hey everyone ~ I got inspiration for this fanfiction from Yoosung's Bad End 1, where he shows of his extremely Yandere side, threatens Seven, and then comes to the apartment, setting off the bomb and killing himself and MC. For some reason, the thought of Yandere Yoosung is really intriguing, and I wanted to write a fanfiction about it. I've never tried writing this kind of story, so here's hoping I do a good job of it! I want to make it as intense and scary as I possibly can. Hehe.

WARNING: This fanfiction contains scenes of explicit gore, IN DETAIL. If you are disturbed by things like this, this may not be the story for you.

I do not own MM.

* * *

Darkness.

There was nothing else. It was everything, and nothing, all at once. It seeped through my fingernails, into my veins, staining my skin, my organs, like ink had been injected inside of me, replacing the blood inside my body. My breath- a farce. My thoughts- an illusion. My existence- a pity. Everything I had needed was stolen from me, by people who didn't deserve to take it.

 _Take it back._

I bit down on my lip as I stared at the screen of my phone, the only source of light in my dark room.

"Hey Babe!"

"Zen!"

I squeezed the phone tighter in my hands.

"I missed you! Where were you today?"

"Oh, I was working and getting back to some guests for the next party?"

"That must have been really tiring. Do you want to come over and I can give you a massage?"

My teeth sank into the skin of my lip, blood dribbling down my chin. I could feel my breaths heaving from my chest, becoming uncontrollable, picking up pace. I clutched at my throat desperately, trying to stop the panic.

I couldn't.

"How about it, Babe?"

 _Don't call her that._

"That sounds amazing! When should I go?"

 ** _Don't go._**

I coughed into my sleeve as I felt blood trickle down my throat, choking me. I pulled my arm back and from the glare of my phone I could see the blood on my sleeve. I stared at it, anger pulsing through my veins.

Red.

Red _Red **Red.**_

The same colour as his eyes.

 _The same colour as the one who stole her._

I turned back to my phone, shaking now. My body was in agony, my skin burning- I wanted to tear it off. I wanted to skin myself.

 _I wanted to skin him._

"You can come anytime you want to, Babe."

"I'll shower first! Hey, isn't Yoosung in here..?"

"Huh? Is he?"

I growled, throwing my phone across the room with all the strength I could muster, and it hit the wall with a satisfying bang, falling down to the floor in pieces. I looked over where it would have fallen, unable to see because of the darkness. I could imagine the pieces, the shattered glass.

 _How nice would Zen's body look in pieces?_

Laughter began to form in my throat. Ironic laughter. Sadistic laughter. I was dead inside, nothing was funny.

Except for my life.

It was a joke.

Everything I had ever loved had been taken from me, I was useless. I couldn't protect the things I loved, no matter how many times they were given back to me.

Rika.

 _Rika._

Rika sent her. I know she did.

 _I deserve her._

My body was quaking, my heading pulsing. I dug my nails into my chest, raking them down, trying to feel something, anything.

Blood.

 _Blood._

 ** _His blood._**

I sank to my knees, my palms on the ground. I could feel it, the darkness- it was taking over. The same darkness I had felt when I lost Rika.

 _When I lost her the first time._

I punched the floor, a sickening crack filling the air, but the adrenaline in my veins was so powerful I hardly took notice.

I deserved her.

I _had earned her._

She was where Rika was. Rika was my family. She was my blood.

 _I deserved Rika's replacement more than anyone._

And Zen- _fucking Zen-_ _how dare he._

How dare he take her from me.

The one who stood where she stood.

The one who did what she did.

She was mine.

 _Mine._

 ** _Mineminemine._**

I was rocking back and forth on my knees, my hands pulling desperately at my hair, tears streaming from my eyes, a sick smile plastered to my face.

Take her.

Take her.

 _Go take her._

 _Do it._

I rose to my feet, my body numb, all except for the need I felt- the hunger.

I walked to the kitchen, reaching into a drawer for what I desired. I smiled as I saw it lying there, glinting back at me.

 _You know what you have to do._

I know what I have to do.

 _You can't lose Rika again._

I won't.

My hand wrapped around the handle of the knife, turning it over in my fingers, accidentally slicing the tip of my finger. I watched, bemused as the blood trickled down my wrist and arm, dripping to the floor.

 _I won't lose Rika again._

 _Not when she's come back to me._

* * *

"Babe?" Zen called from the kitchen, the teapot whistling loudly. "I ran out of your favourite tea- are you okay with chamomile?"

Zen waited a moment, tilting his head when he received no reply.

"...Babe?" He took the pot off the stovetop, turning the heat off. He turned on his heel, looking towards the living room; she wasn't there. He looked down the hall, walking slowly towards the bedroom.

"My princess? You didn't fall asleep, did you?"

Zen laughed under his breath as he pushed the door open, his laugh freezing in his throat as he felt a rush of cool air. Had they left the window open?

"Babe-"

Zen's voice hung in mid-air as his eyes adjusted to the darkness of the room, his heart pounding in his chest. His love was laying on the bed, unconscious, her forehead bloodied- clearly knocked out cold- and next to her, from the glare of the moonlight outside the window, was the blonde-haired silhouette of the culprit, a cool blue outlining his features. Purple eyes reflected from the light of the hall, though the light of the hall was the only light that remained inside their depths- this was an ominous violet, and there was no remorse hiding behind them.

Zen let out a shaky breath, unable to move as he saw Yoosung's lips curve in to a forbidding smile.

"Oh," his voice was low and malevolent, but eerily calm, and Zen felt like his body had been dipped in ice, "Zen, how nice to see you."

Yoosung lifted his hands, twirling his knife in his fingertips, his head tilting gently to the side.

" _I was waiting for you."_

Zen swallowed, his body telling him to step back, to run, but he couldn't. He was frozen with fear, afraid that one wrong move would end it all.

"Y-Yoosung, you... What... What happened...?"

"What happened?" Yoosung asked innocently, before his lips curled back up into a disturbing grin

"Ha... Ha... HhahahahahaHAHAHA!" Yoosung's laugh was not the cheerful tittering Zen once knew- no, this was hysteric, manic, deranged.

"What happened to me?! What happened?!" Yoosung stepped slowly towards Zen, his eyes flashing ominously.

"You know what happened, _lovely Zen."_ Zen flinched as Yoosung spoke, his voice slicing into his ears like a hatchet.

"First," Yoosung chuckled, only a few feet from Zen now, " _First,_ it was V. That _fucking bastard._ If he hadn't existed, maybe I wouldn't have lost her the first time. Maybe I could have kept her."

Zen's brows came together, confused, horrified.

"The first time..? Yoosung- she's not-"

Yoosung darted towards him holding the knife up to his throat and Zen froze, his eyes blasted wide, shaking violently as the cool metal kissed his skin.

 _"YOU DON'T GET TO TELL ME ANYTHING!"_

Yoosung's screams were completely unhinged, full of animosity. He pushed the knife down against Zen's throat, forcing Zen to kneel. Yoosung smiled as he looked down at him, his head tilting, his bangs casting a dark shadow over his eyes.

"No... You dont get to tell me anything. V was the cause for Rika's death. I know this much," Yoosung leaned in, grabbing Zen's ponytail, pulling his head back and Zen gasped, his breaths shallow, his eyes welling up with tears, " _I should have killed V. Then maybe Rika wouldn't be dead."_

Zen took in a slow breath, trying to stay calm. He felt like he was going to vomit any second, terror rippling through him.

"Yoosung... You're making a mistake... Please..."

Yoosung giggled, his eyes still fixed on Zen, staring at him as though he were the prey he had been hunting for many years.

"A mistake? No, no no no." Yoosung suddenly pulled back, kicking Zen in the face. Zen cried out in pain as his head hit the wall, his hands flying up to his jaw as he felt blood fill his mouth, teeth sinking into his tongue. "The only mistake I made was allowing you to take her from me." He placed his foot on Zen's throat, pushing down hard, revelling in Zen's desperate attempts to breathe, his voice strangled in his esophagus.

"She touched what Rika touched. She got to be where my family was. It was like Rika sent her for me, don't you think? _Don't you think I deserve Rika's replacement?"_

Zen grabbed Yoosung's ankle, desperately trying to pull him off, but screamed in agony as Yoosung brought the knife down, slicing his fingers open.

"FUCK-"

Yoosung hardly gave him a second to register the pain before stomping on Zen's offended hand, causing him to scream out once more. Yoosung smild wildly, tears flowing from his eyes.

"Nobody is going to stop me this time. I won't be useless this time. _I will protect her. Nobody else can do this but me."_

Yoosung kneeled over Zen's body, the silver-haired man now petrified beneath him. Yoosung leaned down, using the knife to slice open Zen's shirt, ignoring the noise of pain slipping from his mouth as he cut his stomach just above the surface. Yoosung stared him over, licking his lips slowly, staring at the blood beading where the cut on his abdomen lie.

" _Oh Zen... Zenny Zen. Don't you think you'll look even more beautiful once your skin is the same colour as your eyes?"_

Zen's lip trembled, tears streaming from his eyes, hyperventilating now.

"Yoosung, please, _oh god, please,_ don't- don't-!"

Yoosung cut him off with his crazed laughter, slapping him hard across the face before grabbing his jaw forcefully.

"No, Zen."

He pressed his hand over Zen's mouth, smiling as he lifted the knife high with his other hand, Zen's muffled screams hardly escaping under Yoosung's palm, his body squirming desperately to escape, to no avail.

 **"Nobody is taking Rika from me again."**

* * *

Jumin tapped his elbow impatiently, listening to the ringing of the phone once more, until it once again reached voicemail. He sighed, rubbing his brows in frustration. He turned to Jaehee and Seven, who both looked extremely concerned.

"Did he pick up...?"

Jumin shook his head, stowing his phone away. Jaehee bit her lip, picking at her nails desperately.

"Do you think we should go check on them..? I mean, it isn't like Zen, or her, to not come to the chatroom for two days, or respond to us-! And I asked Zen's manager, and he hasn't shown up to rehearsals... What if they got sick? What if something happened?" She tried to control her voice, but her panic betrayed her as her voice cracked. Seven placed a hand on her shoulder, trying to squeeze it reassuringly, but he felt a pit in his stomach he could not explain.

He looked up at Jumin with concern, inhaling deeply.

"I have a bad feeling."

Jumin nodded, his eyes closing slowly.

"Me too."

"Yoosung wasn't responding to the chats much for the past month, and from what I heard he stopped going to school too. Often times I'd see he was in the chat, but not responding- only watching." Seven bit his lip for a moment before continuing. "I'm... I'm worried that he may have something to do with this."

Jaehee's head shot up, looking at Seven in credulously.

"Yoosung?! But he's the most innocent of all of us-"

Seven shook his head, silencing her.

"That may be so in most cases, but... You don't know how passionate he was about Rika. It was lucky he didn't snap when she died, but I remember him being obsessed with the idea that Rika had sent our new member, and that she was just like Rika. I have a very, v _ery_ bad feeling about this."

Jumin pulled his phone out again, dialling purposefully.

"I'm calling the driver kim and the security guards. We're going to go to Zen's apartment."

* * *

"What do you want us to do, sir?"

"I want you to keep your guns ready. We don't know if something happened, but it may have. So we have to be cautious. Knock on the door first, and if there is no answer after a second time, you break it down. Seven has already checked the security lines to make sure there are no bombs or rigged appliances."

The head of security nodded, walking towards the door of Zen's apartment. He looked back at the other 3 guards behind him, who nodded, their guns out of their holsters and ready to go. The security head knocked on the door loudly.

"Hyun Ryu? Are you in there?"

Silence. He looked back towards Jumin, who nodded, urging him to knock once more. He complied, knocking louder this time.

"Hyun Ryu, this is head of security for C&R International, are you in there?"

They were responded to again by dead air, and he stepped back, in time with the guard next to him, they kicked hard at the door, which broke open beyond the lock by their force.

"Hyun Ry- Oh my _god!"_

The head of security stepped back in shock, his gun falling out of his hands, clattering into the ground at the scene before him. He was pushed out of the way by Jumin, his eyes wide, staring wildly, his mouth hung open, unable to speak.

There, a mere few feet from the door, was Zen- or what should have been Zen- hanging from the roof. His body was tied up in a position that seemed as though he had been crucified, but he was unrecognizable. His skin had been completely cut off, hanging like streamers around the room, his tongue cut in half, his eyes hanging from their sockets. Jumin swallowed, looking up, his hand flying to his mouth as he saw that his intestines were what was hanging him to the roof.

The walls had been painted with Rika's name, over and over, in Zen's blood. Strips of his hair had been used to underline each reiteration of the name, and amongst that, words like _traitor, thief, liar,_ were strewn amongst the mess.

Jumin turned from the door, unable to contain the sickness that had built in his stomach, vomiting next to the door, his head reeling, hardly registering Jaehee's screams and Seven's sharp breathing.

Jumin wiped his mouth, shaking his head. This had to be a sick joke, right? This couldn't be real. It couldn't be.

He got up shakily, his knees weak, barely recognizing the sound of the head of security calling the police desperately. Jumin looked back into the apartment, looking down at Zen's feet, just noticing a note that had been written there, and he had to swallow back bile as he saw that it was written in strips of Zen's skin.

 _I won't lose Rika this time._

* * *

"Uhnnnn... Oh, ow... Oh..." She moaned softly, her eyes fluttering open slowly. "God, my... My head..." She felt like she had been hit by a truck, fuzziness surrounding her body and her mind. She blinked, trying to erase the blurry wake before her, registering a small beam of light. She tried to sit up, and suddenly felt more alert as she realized she was chained to a wall.

She looked at her restraints- metal chains wrapped around her arms and connected to a wall. She pulled at them desperately, fear rising within her. She looked around the room, trying to see something, anything that could explain what was going on.

"H-Hyun..? HYUN!" Her voice was shaking as she cried out, the quivers of her body causing the chains to rattle. She heard footsteps nearing the room, and she felt as though she would choke on the pounding in her chest. Through the light of the doorway at the far end of the room, she saw a figure emerge, and she gasped, confused and alarmed.

"Y-Yoosung..?!"

He smiled as he walked towards her, his body visibly covered in blood. She tried to scoot back as he neared her, but only felt the cold stone wall pressing against her back. He kneeled down before her, smiling gently at her, reaching out to stroke her cheek.

"Hello Rika."

She swallowed thickly, her mouth dry, her voice coming out as a small croak.

"I'm, I'm not Rika... I'm me."

Yoosung glared, grabbing her head and smashing it back against the wall. She screamed in pain, his nails piercing her scalp. His eyes were deranged, devoid of all emotion except for the madness that remained.

"Rika sent you here for me. She knew I was lost after she left, so she gave me you," His smile seemed almost dreamy for a moment, until it was replaced again by one of malice, "But _Zen tried to take you from me, just like V took her."_

"N-no.. Wait.. Hyun- Hyun!" Tears formed in her eyes as realization struck her.

The blood.

 _The blood._

"WHAT HAVE YOU DONE TO HYUN?!"

Yoosung chuckled, petting her hair.

"Oh, Rika, don't worry about him. He won't bother us anymore."

"No-no! I'm not Rika- I'm not- what- What have you done.. Oh god..."

She pulled at her restraints desperately, her head falling forwards, and she finally caught a glimpse of her hair, gasping as she saw it was no longer the brown it had been her entire life, but was now replaced with blonde. She glanced at her clothes- a green dress had been put on her body.

He had tried to make her look like Rika.

Her head lifted, meeting his sinister gaze, her lip trembling.

"Why are you doing this to me?"

"Because I love you, Rika."

"I am not Rika!"

"She sent you to be her replacement."

"The hacker is the reason I was brought to the RFA," She gasped, speaking through her desperate tears, "Not Rika! Rika is DEAD!"

Yoosung smiled, tilting her chin up, squeezing it roughly.

"Rika lives through you. I can feel it."

He reached for a strand of her hair, running it through his fingers, causing her to flinch away as best she could.

"You look so much like her like this..." His smile fell as he stared into her eyes. "This is a problem, though."

He got up, taking a few steps away to a table that was nearby, turning back to her, his head tilted curiously, his eyes dark as he looked down at her.

"Your eyes don't look like hers."

She gasped in fear, shaking her head, vomit rising in her throat.

"No, no no, oh god no please- don't, please don't!"

Yoosung growled as he walked towards her.

"You're saying the same things he said. Why, Rika? Why are you betraying me?"

"Because I am not Rika!"

Yoosung wrapped his hand around her throat, pressing her back against the wall, his smile dark and domineering.

" _No. You are her reincarnation._ "A laugh escaped his lips as he squeezed her neck, digging his nails into her skin, "When I see you here in front of me, I feel as if I am with Rika again. I'm so jealous... You got to be where she was. You got to see what she touched, be where she _lived._ _You get to live her life."_

Yoosung let go, twirling his knife in his hands, staring at it with an almost solemn expression.

"V couldn't protect Rika. I should have gotten rid of him. I never trusted him- If she had just stayed by me, I could have protected her. _I could have protected you,"_ his eyes flicked up to meet hers, and she swallowed, her tears flowing freely from her eyes, _"I won't let anybody else take you from me. I will make sure you get to be happy,"_ he grinned, his eyes half-lidded as he traced the knife along her cheek, his voice a mere whisper, _"unlike Rika."_

She kept still as best she could, afraid to press the knife to her skin any further, trying to find words, say something, anything.

"Y...Yoosung... What are you... What are you going to do?"

Yoosung smiled at her, staring into her eyes.

"I'm going to make sure you don't look at anyone else."

* * *

 _"Mmm hello?"_

"Yoosung," Jumin stared at Seven, afraid to look away as he had finally gotten through, "Where did you take her?"

 _"That's none of your business."_

"If you tell us now, if you let her go, I can keep you out of the electric chair for what you've done. You'll just spend life in prison, rather than getting killed, you just have to tell us where you are."

 _"Hmmm~ I don't really like that deal."_

Jumin froze as he heard soft cries in the background, the pit in his stomach growing wider.

"What did you do to her?"

Yoosung laughed softly through the phone, an appreciative noise escaping his lips.

 _"I made sure she won't see anyone else but me."_

"Yoosung, fucking hell-" Jumin's resolve broke, he was desperate now, hoping those words didn't imply what he thought they did, "What do you think you're doing-?! You need to stop this! This isn't you!"

 _"You can thank V for me. And tell him that it's too bad I didn't find him before Zen. He would have looked nice next to him."_

"Yoosung-" Jumin froze as the line cut off, his breathing ragged, and he threw the phone at the ground, scared, angry.

"He.. He has her...?" Seven's voice was shaking, timid, afraid of the answer he already knew.

Jumin looked at him, his head shaking, pain pulsing through his heart.

"I think... She is alive, right now... But... I think that he cut her eyes out."

Jaehee choked in a corner, leaning over a garbage can- she was unable to stop her hysterics since leaving Zen's home, her body retching uncontrollably. They were at the police station, waiting desperately in hopes that they could find Yoosung before it was too late.

But they already knew it was too late long ago.

* * *

 _"Rika, you are so beautiful."_

Yoosung hummed to himself as he tilted her head, her cries having stopped long ago, her body too exhausted with pain to respond. He placed his hands on either side of her cheeks, stroking them softly.

"You look much nicer being unable to see. It makes me happy knowing I was the last person who you got to see, Rika _. It never should have been V."_

He pulled out a key, inserting it into the locks of her restraints, her body falling limply to the ground. He clicked his tongue, wrapping his arms around her, helping her sit up by leaning her body against his own, making her legs straddle his knees, which were folded underneath him.

"Oh, Rika, you're exhausted. Maybe you worked too hard?" He stroked her hair, her breathing shallow against his neck, which was slowly becoming wet with the blood dripping from her eye sockets. "You need to rest for a long time. You deserve it."

He smiled, nuzzling his face into her hair, breathing in the scent of her shampoo.

"I'm glad I kept buying the shampoo you used to use. I knew it would come in handy someday."

He kept one arm wrapped around her waist, supporting her, and his free hand reached off to the side, wrapping around the object of which he needed next. He moved back, leaning his forehead against hers, staring into the now empty sockets where her eyes once were.

 _"Rika,"_ He lifted his hands behind her back, holding the sharp metal spike behind her back, pressing it against the wall for leverage. He smiled maniacally, his lips close enough to hers to feel her breath ghosting over his own, _"We will never be apart again."_

He used his legs to his advantage, pushing up on his knees, putting all of his strength into it. The spike pierced through her chest, and soon through his own, and as he finished pushing, her body was against the wall, his pressed firmly against her own, the pipe holding them together through their chests. He felt hazy, the poison he had painted on the pipe earlier making him dizzy. He heard her breathing slowing, becoming more shallow as death crept over her, and he leaned up as much as he could, pressing his lips against hers as he felt the remnants of his own life-force draining away.

 _"I love you, Rika."_ He leaned his forehead against hers, smiling as everything went black.

 _"Let's be together forever."_

* * *

WEOOOOO Okay that was really difficult to write. I was listening to creepy music the whole time to try and emphasize the emotions I wanted to produce. ;;

I hope you liked it! Again, this was my first time trying out a fic like this, so I apologize if it isn't the best. I just wanted to give it a try! :3 It was fun, in a strange way.

Let me know what you think!

Stay Rad, guys!

~Pixil-8.


End file.
